The National Do Not Call Registry allows consumers to register their phone numbers to reduce unwanted telemarketing calls. Registering a phone number adds it to a list that telemarketers must remove from their call lists. While registration significantly reduces telemarketing calls, it does not stop all unwanted calls such as those from charities, surveys, or with whom the consumer has an existing relationship. Consumers can file complaints about telemarketing calls received after being registered for over 31 days.